serialize commas datetime field Drupal 8

field--field-event-date.html.twig

{% for key, item in items %}
{% if loop.length == 0 %}
        {% set separator = loop.last ? '' : '' %}
        {% elseif loop.length == 1 %}
        {% set separator = loop.last ? '' : '' %}
        {% elseif loop.length == 2 %}
              {% set separator = loop.last ? '' : ' and ' %}
        {% elseif loop.length == 3 %}
              {% set separator = loop.last ? '' : ' bot '  and loop.index == 2 ? ', and ' : ', ' %}
        {% elseif loop.length == 4 %}
              {% set separator = loop.last ? '' : ' toy ' and loop.index == 3 ?   ', and ' : ', ' %}
        {% endif %}
{% if loop.last == false %}
            {% set eventDate = item.content['#text']|date('F j') %}
            {{ eventDate }}{{separator}}
        {% elseif loop.last == true %}
            {% set eventDateYear = item.content['#text']|date('F j, Y') %}
            {{ eventDateYear }}{{separator}}
{% endif %}
{% endfor %}